1. Technical Field
The present invention relates to a projector.
2. Related Art
FIGS. 9A to 9C are all a diagram for illustrating a projector 900A of a typical type. Specifically, FIG. 9A is a diagram showing a system of the projector 900A, and FIGS. 9B and 9C are both a diagram for illustrating problems of such a projector 900A.
The projector 900A is provided with liquid crystal devices 400R, 400G, and 400B for use as electro-optic modulators, each serving as a hold-type display unit with such luminance characteristics as shown in FIG. 9B. Unlike an impulse-type display unit with such luminance characteristics as shown in FIG. 9C, e.g., CRT, the hold-type display unit has a problem of not-smooth moving image display due to a so-called persistence of vision. As to the persistence of vision, refer to Non-patent Document 1 (“Quality of Moving Images Displayed on Hold-type Display”, Technical Report of The Institute of Electronics, Information and communications Engineers, EID99-10, pp. 55–60 (1999–06)), for example.
As a measure taken against the above-described problem, Patent Document 1 (JP-A-2002-148712 (FIGS. 1 to 7)) describes an exemplary projector. FIGS. 10A to 10C are all a diagram for illustrating such another typical projector 900B. Specifically, FIG. 10A is a diagram showing a system of the projector 900B, and FIGS. 10B and 10C are both a diagram showing an optical shutter for use with such a projector 900B.
As shown in FIG. 10A, the projector 900B includes optical shutters 420R, 420G, and 420B on the light incident-side of the liquid crystal devices 400R, 400G, and 400B to cut off the light in an intermittent manner, attempting to correct the so-called persistence of vision to derive smooth moving image display high in quality.
The issue with such a typical projector of Patent Document 1 is that the light use efficiency is considerably reduced due to the optical shutters cutting off the light in an intermittent manner.